I've put together a quick gallery at the top of the page highlighting differences between the low, medium and ultra presets built into the graphics options. You'll need to view them full-size to see the difference, especially if you're looking for the gap between medium and ultra settings.
The Witcher 3 looks surprisingly good on medium settings, which is good news if you don't have a mega-rig. The low setting preset looks okay in these still shots, but there's a lot of foliage and character pop-in that's very distracting when the game's in motion. Textures on NPCs, particularly clothing, suffer on low settings, and you'll notice some blurriness at medium. At ultra the foliage is plumper and there's a lot more of it. A lot of the high-end effects, like HBAO+ postprocessing and ultra shadows, are very subtle improvements for a noticeable framerate hit. The game still looks great even if you can't put everything up to ultra.
We'll get into some more detailed framerate tests as our review progresses, but here's how it performs up on my office machine—GTX 970 GPU, i5-2500K CPU (4x3.3GHz), 16GB RAM. Ultra: 40 - 50 FPS, dropping to near 30 in some conversations. Disabling HairWorks immediately adds 5-10 FPS, dropping shadows down to from ultra to high in addition gives smooth close-to-60 performance. Medium: 70-100 FPS Low: 100-120 FPS
